Automatic transport devices often transport a plurality of goods in objects which must be individually identified to be properly sorted. Parcels, such as airline baggage, shipping containers, production inventory, machine parts, and component parts, are often identified with flexible tags or labels. Electromagnetic sensing is sometimes used to identify the flexible tags or labels on individual objects placed upon a conveyor. When the objects are oriented so that the identification tags are located beneath the object on a conveyor, they cannot be read by conventional line of sight reading equipment located above the conveyor.
U.S. Pat. No. 5,450,492 issuing to Hook et al. on Sep. 12, 1995 is representative of an electronic identification system having a transmitter for generating an electromagnetic excitation signal, and one or more transponder s with variable time and frequency.
U.S. Pat. No. 4,724,953 issuing to Winchester on Feb. 16, 1988 discloses a food conveyor apparatus having a plurality of rows of oblong holes positioned along the length of the conveyor, with each row offset from adjacent rows of holes. The platform supports an endless mesh conveyor band. The plurality of holes and the endless mesh conveyor band allow food debris to fall through the conveyor band and platform to simplify cleaning in a food processing environment.
U.S. Pat. No. 5,040,549 issuing to Ray on Aug. 20, 1991 discloses a band conveyor for feeding tobacco into a cutting machine. A plate supporting the conveyor band has a plurality of apertures through which debris may fall or be swept, and a means below the plate to collect the particulate material.
To be effective, the identification tags on individual objects must be oriented to position the identification tags in relation to the reader antenna positioned in proximity to the conveyor band. Manual orientation of the objects to orient the identification tags in relation to reader antenna is labor intensive and time consuming. Where the identification tag is positioned beneath the object, it cannot easily be read by reader antenna positioned above the conveyor. Thus, what is needed is a way to position the reader antenna beneath the conveyor band to read identification tags located beneath the object.